1Melnikov permafrost institute SB RAS, Russia
2University of Warsaw, Poland
The paper considers periglacial sediments within Abalakh high accumulative plate (AHAP) in Central Yakutia. This territory occupies Lena-Amga interfluve. In borehole 18/1 five Complexes (I-V) of sediments was recognized: alluvial in the bottom (Complex I), overlaying by alluvial-lake sediments (Complex II), lake (Complex III) and Ice Complex (Yedoma) ((Complex IV). The top of sediment succession is occupied by the Holocene deposits (Complex V). Micromorphology of quartz sand and silt grains analyzed in scanning electron microscope (SEM) and mineralogical analyses were introduced to reconstructed accumulation conditions, influence of periglacial conditions and source of sediments. Based on the obtained results, it can be concluded that the accumulation of deposits of the Complex I took place as a result of multiple retransporting of the same material and a limited supply of new material in a fluvial environment. Up the profile, the activity of fluvial processes decreased in favor of lake accumulation. Syngenetically frozen ice-rich silty deposit (Yedoma, Ice Complex) of the Complex IV is made of grains with a precipitated surface, but with a different degree of crusting and mineralogical different from the deposits lying below. Aeolian processes are responsible for their transport. They are a compilation of a variety of sediments, including supply older sediments, including retransported loess, and mechanical weathering took place in parallel with sediment accumulation.
Anna Kut, PhD, researcher of the Melnikov Permafrost Institute (Yakutsk, Russia). Key points of studying is reconstruction of sedimentation environment of the Ice Complex sediments within Central Yakutia and Arctic region and frost weathering processes in sediments in the Pliestocene and Holocene sediments and its regional manifistation. Using method is morphoscopy analyze is based on the roundness degree and frosting of quartz grainʼs surface rating.
The Center for Ecological-Noosphere Studies of NAS RA, Armenia
Mercury (Hg) contamination is a progressively noticeable issue in environmental research, especially for the most vulnerable urban population group – for children. In this relation, the potentially important exposure sites for children like kindergartens require special focus. The objectives of this study were to evaluate Hg pollution levels and assess related child health risks of 19 and 22 kindergarten soils of two young industrial cities in Armenia - the cities of Vanadzor and Gyumri, respectively.
Hg concentrations in soil samples retrieved from Vanadzor and Gyumri were significantly low constituting 0.025–0.05 mg/kg and 0.03- 0.11 mg/kg, respectively. The total concentrations of Hg were determined using XRF-spectrometry (Olympus Innov-X-5000).
In the case of Gyumri, Hg maximum content exceeds the background value (0.07mg/kg) with about 1.57 times, Hg mean content (0.046) does not exceed.Excesses vs. MAC stated in Armenia (2.1 mg/kg) were not observed for both city kindergartens.
According to the coefficient of concentration (Kc), the pollution level classified as Kc < 4 indicating an allowable level in both cities. The pollution source analyses suggested comparatively high Hg concentrations only in three Gyumri kindergartens soil, possibly influenced by the impact of anthropogenic activity. In remaining 19 and all Vanadzor kindergarten soils, Hg concentrations had a natural origin.
According to the Potential Ecological Risk Index (PERI) a moderate risk level was detected only in 5 kindergartens of Gyumri. The results of the health risk assessment indicated the absence of an adverse health effect to children associated with the Hg contents.
Gayane Melkonyan has her expertise in the evaluation of environmentalgeochemical investigations. Her academic background includes a Bachelorʼs and a Masterʼs degree with honor from Yerevan State University, faculty of biology, department of Biophysics. Currently, she is a Ph.D. student in Geoecology in the Center for Ecological-Noosphere Studies NAS RA. Her research has concentrated on the assessment of Hg pollution levels and associated potential risks in different urban and mining areas of Armenia, aimed at obtaining an improved understanding of the processes controlling the biogeochemical cycling and environmental distribution of mercury, as well as the identification of vulnerable risk groups in the population.